GSSI Testing In Boston

I am back from Boston and had quite an experience with the GSSI testing at the Boston marathon expo on Saturday. First, I did not get to meet Bill Rodgers. The organizers told me late Thursday that he rescheduled for Sunday and instead I would be running alongside Olympian Alistair Cragg, but that didn’t pan out either since there was only one working treadmill.

I showed up about an hour early and discovered the ‘mobile lab’ was actually right in the middle of the expo which I was not expecting. For some reason I envisioned a trailer or a truck outside of the expo, something private. I had emailed the organizers and asked if my friend could come take pictures and they politely told me that they would take pictures and email them to me, which I took as a no and assumed again that it would be in a private setting. Wrong! It was in the middle of literally thousands of people at the expo which was intimidating and gave me butterflies. I was told to fast for four hours before the test so I also had the beginning of a hunger headache coming on.

I caught the tail end of Cragg’s session while waiting for mine and he was running a 5 minute per mile pace. One of the reps was announcing his speedy pace as well as all of his accomplishments over a loudspeaker as many people stopped to watch, ask what he was doing, etc… Again, I wondered what I got myself into and almost slipped quietly away. Fortunately, the onsite GSSI staff was very supportive and encouraging, telling me not to worry about my pace and even assured me that they had an earlier tester who walked, not ran on the treadmill.

Once it was my turn I had to provide a urine sample to measure my hydration, I was weighed, my height was measured, put on a heart rate monitor, and my head was fitted for the gear to hold the mask in place. I had to put nose clips on so I was not able to breathe through my nose at all. Then the mask came on to capture all of my expired air. The mouth piece was similar to something for a snorkel with inserts to bite down on – somewhat uncomfortable but bearable. The tubes on each end of the mask were long and heavy so someone had to stand on each side of the treadmill and hold up the tubes to alleviate my jaw/mouth of that extra weight.

The GSSI physiologist, Kim White, explained I would be doing a sub maximal test, not a VO2 max test. I ran on the treadmill for 30 minutes, starting at a 12 minute per mile pace, increasing half of a mile every five minutes, running the last 5 minutes at an 8 minute per mile pace. Normally that would be a fairly easy run for me, but with the awkwardness of the mask and my nerves it seemed difficult. One good thing about my petite stature is that I couldn’t really see the expo crowd over the treadmill (and they probably couldn’t see me too well either) so I once I started running I forgot about the crowd and instead focused on trying to breathe through the mask without drooling.

I was relieved to be done and extremely thirsty – had very bad case of dry mouth from the mask. I was given a 16 oz bottle of Gatorade Recover which I drank about half of. When I was weighed again after the test my weight was exactly the same (optimal result) so Dr. White indicated what I drank was exactly what my body needed – about 8 ounces of fluid to replenish what I lost while running.

Dr. White from GSSI going over results with me after testing over.

Dr. White then went over the results with me – since I did get to about 98% of my max heart rate she estimated my VO2 Max at 45.7, which for my age is very good. I burned 301 calories overall, and at the 9 minute per mile pace I was burning about 140 grams of carbohydrates per hour. Since I am targeting about that pace for my Burlington marathon pace that is what I was focusing in on. Dr. White indicated that my body can really only use approximately 90 grams of ingested carbohydrates per hour, so for my marathon I should take about 25 grams right before the race begins, and then start ingesting as soon as possible, trying to target about 90 grams per hour, and not waiting to get a hour into the race which I had read before. The Vermont City marathon is offering Gatorade endurance formula at each of the stops which for a cup ~3/4 full will provide me with ~15 grams of carbohydrates, so I should plan to drink about one offered cup at each stop. Lots of articles/information point you to getting your body used to whatever the marathon will be offering so I have to start buying the lemon/lime flavor, which is definitely not my preference – I usually go for the orange flavor.

If you are interested in reading the full report GSSI provided me you can view it here.